1. Field of the Invention
The present invention relates to an imaging apparatus, a moving body detecting method, a moving body detecting circuit, and a program which are suitably adapted to, for example, a case of detecting a moving body.
2. Description of the Related Art
There is an imaging apparatus for a monitoring purpose, which can image a subject with visible light or infrared light. An image picked up by the imaging apparatus shows various things which are individually specified by a process for a computer device to identify them as objects. The computer device adds various kinds of information to an object to facilitate subsequent image processing.
There is also a monitor system which enhances the security performance by specifying an intruder from an image picked up by a monitoring imaging apparatus. Such a monitor system detects an intruder by detecting a moving object as a moving body with respect to the background contained in the image. This allows the monitor system to catch and detect an intruder whose slight motion may be overlooked merely by human visual monitoring, and the motion of an intruder whose density matches with that of the background.
In the foregoing description, “moving body” includes a body which moves (e.g., the overlaid portion of an object changes by 10% or more every frame ( 1/15 second)) or a body which moves after temporary halting.
JP-A-2001-8189 (Patent Document 1) discloses an art of detecting a moving object by tracking an object candidate obtained from a change in luminance acquired from the difference between a directly previous image and an original image.
JP-A-11-41589 (Patent Document 2) discloses an art of performing density pattern matching on a change area extracted from the difference between images between two frames, regarding the change area as a disturbance when a similarity therebetween is higher than a predetermined value, and detecting the change area whose similarity is low as a moving object.